Add chrony (NTP) support for SLE 15.

Since SUSE Linux Enterprise Server 15, chrony is the default
implementation of NTP (
https://documentation.suse.com/sles/15-SP6/html/SLES-all/cha-ntp.html
).

This commit adds support for using chrony instead of ntp in SLES
versions >= 15.

See merge request nexedi/slapos.package!202

playbook/roles/ntp/meta/main.yml

@@ -6,7 +6,8 @@ dependencies:
     package_state: present
     when: ( ansible_distribution == "Fedora" and ansible_distribution_major_version|int < 34 ) or
           ( ansible_distribution == "Ubuntu" and ansible_distribution_major_version|int < 23 ) or
-          ( ansible_distribution != "Fedora" and ansible_distribution != "Ubuntu" )
+          ( ansible_distribution == "SLES" and ansible_distribution_major_version|int < 15 ) or
+          ( ansible_distribution != "Fedora" and ansible_distribution != "Ubuntu" and ansible_distribution != "SLES")
 
   - name: Install ntpsec package
     role: package
@@ -14,3 +15,9 @@ dependencies:
     package_state: present
     when: ( ansible_distribution == "Fedora" and ansible_distribution_major_version|int >= 34 ) or
           ( ansible_distribution == "Ubuntu" and ansible_distribution_major_version|int >= 23 )
+
+  - name: Install chrony package
+    role: package
+    package_name: chrony
+    package_state: present
+    when: ansible_distribution == "SLES" and ansible_distribution_major_version|int >= 15
\ No newline at end of file

playbook/roles/ntp/tasks/main.yml

@@ -8,3 +8,7 @@
   - name: ensure ntp is runing (RedHat)
     service: name=ntpd state=started enabled=yes
     when: ansible_os_family == "RedHat"
+
+  - name: ensure chronyd is runing
+    service: name=chronyd state=started enabled=yes
+    when: ansible_distribution == "SLES" and ansible_distribution_major_version|int >= 15